It is known that in the case of the active immunization the cells used often only show weak or no immunogenicity. This is found particularly when tumor cells are employed.
Experiments were made to increase the immunogenicity of cells. As in the use of oncolyzates obtained by Newcastle Disease Virus (referred to as NDV hereinafter), such experiments often failed to yield satisfactory results.
Thus, it is the object of this invention to provide a composition by which the immunogenicity of cells can be increased.